Just reporting on experimentation with the Dyverso Spline Emitter - Because this is an interesting question raised by JYH126.....

After working with the Spline Emitter (Dyverso) for awhile, I would continue to recommend the use of a Helper Object to shape a free form liquid such as for the goal of JYH126's project. I make this recommendation simply on the basis of ease of use and the amount of effort needed to achieve his (or her) objective.

The Spline Emitter does indeed allow you to create variable "thickness" for each control point. But it is somewhat tricky (difficult) to use for this purpose and I'm not sure that it gives good results without an lot of work and experimentation.

I also experimented with adding many more control points to my spline, which helps a little bit. I tried some other things, such as increased density, and that helps by a small amount. (I did learn that a quick way to increase density is to use the general "Thickness" control for the entire spline, since that acts as a multiplier for whatever thickness values are set for each control point. (A good thing to know.)) I suspect that the best way to control the variability of this emission pattern seems to be to greatly increase the number of control points and reduce the time step interval and the number of scale points between the control points. Combining these things with tweaks of density may finally give a good result.

My conclusion is that these features of the Spline Emitter are wonderful for some uses as they give the user exact control over the particle emissions along the spline. And because each control point is animatable, this is a great tool for some purposes. But for the goal of JYH126's project, it seems much simpler to use a Helper Object to shape the stream of particle emissions from a standard Dyverso emitter.

The only thing I might add to JYH126's WIP is that he or she use a longer emitter and a wider/longer helper object to create a broader particle stream.

Thank you again, Thomas for your information. The Spline Emitter seems like a very useful tool, given the exact control over the emissions of its individual control points. I've learned a lot from you today!